EVALUATION OF TUBERCULIN TESTING AND MEASLES PROPHYLAXIS PROCEDURES USED IN RHESUS MACAQUE QUARANTINE CONDITIONING PROTOCOLS

Twenty-three of 103 adult rhesus macaques (Macaca mulatta) entering NI H holding facilities with no history of measles vaccination or infecti on, no titer to rubeola virus, a minimum of four negative results of i ntrapalpebral tuberculosis tests, and negative for Herpesvirus simiae and type D retroviruses were selected to evaluate the adequacy of comm only used quarantine/conditioning protocol procedures. One month after sensitization by subcutaneous inoculation with 100 mg of killed Mycob acterium tuberculosis in oil, an intrapalpebral tuberculosis test was administered in the right eyelid. Ah animals had reactions that ranged from grade II to grade V. The animals were then randomly allotted to three groups. Ten animals were inoculated with a rubeola-containing ve terinary vaccine (VET), 10 were inoculated with a human measles vaccin e routinely used in macaque quarantine procedures (HUM), and 3 were us ed as unvaccinated controls. Intradermal tuberculosis tests were admin istered in the left eyelid and the skin of the abdomen at vaccination (day 0), and subsequent abdominal skin tests were performed on days 5, 14, and 28. In addition, intrapalpebral tests were conducted an day 2 8. A higher response in the rubeola antibody enzyme-linked immunosorbe nt assay (ELISA) optical density (OD) results was observed in the VET- inoculated group at 14 days after inoculation. More significantly, two members of the HUM-vaccinated group had negative ELISA results after a single dose of vaccine. Three other members of the HUM-inoculated gr oup had ELISA results that were near the OD cutoff value (0.15) and we re retested by the measles indirect fluorescent antibody (IFA) test. R esults for two of these animals were equivocal, whereas that for the t hird was positive. Two of the VET-inoculated group also had results ne ar the OD cutoff value and retested positive by LFA. After administrat ion of a 0.5 mi vaccine booster, the four HUM-inoculated animals testi ng negative or equivocal had ELISA OD values comparable to those in th e VET-inoculated group after administration of a single dose of vaccin e. All vaccinated animals had positive results of intradermal tubercul in tests at day 0 (48 h reading), although 10 of 10 VET-inoculated ani mals and 6 of 10 HUM-inoculated animals had below-baseline responses. At day 5, 3 of 10 HUM-inoculated animals tested at their baseline valu es, whereas 1 of 10 VET-inoculated animals tested positive at the base line value. (The reactive HUM-inoculated animals would later have equi vocal or negative values for measles tests and the VET-inoculated anim al would have a few-positive result.) The control group had positive r esponses at both intervals. At day 14, 8 of 10 HUM-inoculated animals tested positive at baseline values, whereas values in 6 of 10 VET-inoc ulated animals had returned to baseline, At day 28, values in all anim als in both groups had returned to baseline. Small group sizes prevent ed statistical analysis of the immune response other than to confirm t hat the VET vaccine provided at least as adequate protection as did th e HUM vaccine (at a lower cost). However, a strong negative correlatio n was seen between the response to vaccination and the response to sub sequent tuberculin skin testing.